Finding the Fourth Proportional to 2,599.80, 3,587.72 and 1,420.87

Step by Step Solution

1. Step 1: Write the proportion equation
   2,599.80 : 3,587.72 = 1,420.87 : x
2. Step 2: Convert to fraction form
   2,599.80/3,587.72 = 1,420.87/x
3. Step 3: Cross multiply
   2,599.80x = 3,587.72 × 1,420.87
4. Step 4: Simplify right side
   2,599.80x = 5,097,672.27
5. Step 5: Solve for x
   x = 5,097,672.27/2,599.80
6. Step 6: Final answer
   x = 1,960.80